Mid-week quiz: Earlier in the week I asked you what this was. Answer after the article.

Part one can be found here.

In the darkness one of the midget submarines, I-20b, crewed by Lt Akieda Saburo and PO1C Takemoto Masami slipped into the harbour. Only two ships were on patrol at the mile wide harbour entrance. It's no wonder they missed the six foot wide submarine.
Type A Midget submarine as carried by a Japanese sub.
Lt Saburo piloted his tiny craft to a point where he could get a shot in at HMS Ramillies. His first torpedo ran true and impacted just forward of A turret, ripping a 20-30 foot hole in the side of the ship. Although taking on a list and having to flood their magazines the battleship remained afloat, saved by its anti-torpedo bulges.
However the sudden loss of weight caused by the firing one of the torpedoes meant that I-20b was suddenly buoyant and floated to the surface. An Indian lookout on the nearby tanker British Loyalty spotted the conning tower of the submarine. Someone on the tanker managed to get an anti-aircraft gun pointed in the direction of the midget submarine and squeezed off a burst. The volley flew wide and the submarine submerged before he could re-aim.
Tanker British Loyalty
The British escorts then started steaming about dropping depth charges and trying to find the Japanese midget. But the shallow waters frustrated the ASDIC system. Remarkably Lt Saburo stayed in the harbour, and manoeuvred for a killing shot on HMS Ramillies. He lined up his second shot and fired. The torpedo ran true again, however just before impact the British Loyalty steamed in-between the torpedo and the battleship. The tanker had been making a break for open water to avoid being torpedoed, however, this meant that she was in the wrong place at the wrong time for her, but inadvertently saved HMS Ramillies.

With both the I-20b's torpedoes gone Lt Saburo set course for the open sea, and the rendezvous point. However they didn't get far as their batteries were depleted. With no power the two Japanese sailors set their scuttling charge and left the boat but the charge failed to detonate. Both men reached the shore, where they approached natives and asked to be ferried to the mainland, which the natives happily helped them with.
Their new plan is to reach a rendezvous point on the northern tip of the island, to be picked up by their mother submarine.
The only picture I could find of the Crew. Lt Saburo is seated.
At 1100 on the 1st of June both Japanese sailors approach locals in Anijabe village. They explained they're enemies of the British, but allies of the French and wish to avoid the British forces. They also attempted to purchase food, then leave the village.

One of the locals immediately went and found a patrol of British soldiers, these were from 5 Commando. The native explained about the visit of a pair of odd looking Chinese men, with pistols and curved swords, it appears the native wanted a payment for the information.
The Commandos set off in pursuit of the Japanese and cornered them at Amponkarana Bay. The Commandos asked the Japanese to surrender, but they ducked into cover and opened fire, killing one of the Commando's. After a short firefight there is a lull, and two shots rang out. Both Japanese sailors had shot themselves instead of risking capture.
Despite a prolonged search the Japanese mother submarines couldn't find any sign of the two midgets they launched. Eventually the subs left the area, apart from I-20 which stayed on station until the 3rd of June. On that day I-20 spent the day on the surface firing flares trying to signal the midget crew. Eventually as dark fell I-20 left the area.
In 1972 a monument was erected at the site of the Japanese officers deaths. In 1976 a more official plaque was set up.

Image credits:
www.pacificwrecks.com and www.combinedfleet.com

Quiz answer:
It's a Challenger.... An A30 Challenger to be exact. Designed to investigate the way remote vision and laying work. The gun is a 75mm recoilless rifle.